How to make a complaint

If you have a complaint about any aspect of your service, you can contact Colt by any of the below listed methods.

Please provide the following information:

  • The main details of your complaint
  • Your Colt account or circuit number (existing Colt customers only); and
  • Your name and telephone number

Complaints information by country

Country Telephone Postal Address
United Kingdom 0800 358 3999 / +44 207 862 6087
(Monday to Friday, 8:30am - 5pm)
Customer Service
Colt Technology Services
Colt House
20 Great Eastern Street
Austria 0800 880 990 / +43 1 253 07 02
(Monday to Friday, 9am - 5pm)
Colt Technology Services
Kärntner Ring 10-12
1010 Wien
Belgium 0800 507 01 / +32 2 790 16 29
(24 hours)
Customer Service
Colt Technology Services
nv Culliganlaan 2 H
B-1831 Diegem
Denmark +45 70 71 25 99
(24 hours)
Colt Technology Services A/S
Borgmester Christiansensgade
55 2450 København SV
France 0800 948 888 / +33 1 709 95 600
(Monday to Friday, 9am-5pm)
Colt Technology Services
Customer Service
23-27 rue Pierre Valette
92247 Malakoff Cedex
Germany 0800 182 2233 / +49 69 56606 9000
(24 hours)
Colt Technology Services GmbH,
Gervinusstrasse 18-22
60322 Frankfurt
Ireland 1800 944 040 / +353 01 536 9312
(Monday to Friday, 9am-5pm)
Colt Technology Services Limited
One Gateway, East Wall Road
Dublin 3
Italy 192 090 / +39 0289634895
(Monday to Friday, 9am - 5pm)
Colt Technology Services
S.p.A.Viale Jenner,
56 20159 Milano
Netherlands 0800 265 8023 / +31 20 798 0000 Colt Technology Services B.V.,
Van der Madeweg 12-14a
Postbus 94014
Portugal 808 780 222 / +35 1 211 202 795
(De Segunda a Sexta-feira: das 9h00 às 18h00)
Estrada da Outurela,n.º 118,
Ed. B1, Parque Holanda,
2790-114 Carnaxide
Spain 901 888400 / +34 91 7887520
(Monday to Friday, 9am-1pm and 2pm-6pm)
Colt Technology Services SAU
Customer services
C/ Telémaco nº 5
28027 Madrid
Sweden +46 8781 8383
(24 hours)
Colt Technology Services
ABBox 3458
103 69 Stockholm
Switzerland 0800 560 560 / +41 58 560 1720
(Monday to Friday, 9am - 5pm)
Colt Technology Services AG
Bahnhofplatz 1,
8001 Zürich
Livro PT link

Electronic Complaints Book (Portugal Only)

As of July 1st 2017, a new Digital Platform which allows consumers and users to submit their complaints in electronic format is available at, with the same value as the complaints submitted in physical format. The so-called “Electronic Complaints Book” (“Livro de Reclamações Electrónico”) was created by Decree-Law 74/2017, of June 21st 2017 and regulated by Regulation 201-A/2017, of June 30th 2017.

Voice complaints, spam & phishing

If you received unwanted calls or your number is being spoofed, blocked or labelled as potential spam, please contact us at using our form below. For a fast and efficient collaboration, don't forget to provide us your full contact information and a detailed description of the issue that you encountered.

How to escalate if your issue remains unresolved

If your complaint remains unresolved after eight weeks, subject always to any other timeframe as specified by applicable law, or if we agree in writing that the dispute should be settled by Alternate Dispute Resolution (ADR) you can contact one of the following organisations:

Ombudsman information by country

Contact Details
United Kingdom Ombudsman Services 0330 440 1614
[email protected]
Ombudsman Services: Communications
PO Box 730
Warrington WA4 6WU
Ombudsman Services is a third party arbitrator and they will take evidence from both you and Colt to make an independent decision based on the merits of the case. Ombudsman Services will only handle disputes for businesses with ten employees or fewer.
Austria Rundfunk und Telekom Regulierungs GmbH („RTR“) 0810 511811
(EUR 0.07267/minute)
Mon-Fri, 8am-5pm
Rundfunk und Telekom Regulierungs-GmbH Schlichtungsstelle Mariahilfer Straße 77-79 1060 Wien A deadline may be set for the RTR to act. This will need to be met if your enquiry is to be processed. When you receive our response, please verify the existence of any such deadlines immediately.
Belgium Ombudsdienst voor Telecommunicatie / Service de médiation pour les télécommunications +32 22230909 / +32 22230606

[email protected]; [email protected];

Koning Albert II-Laan 8 Bus 3 te 1000 Brussel / Boulevard du Roi Albert II 8 Boite 3 1000 Bruxelles No additional information
Denmark Teleankenævnet +45 33186900
[email protected] or
Teleankenævnet Nørre Voldgade 48, st. 1358 København K The Danish complaints body "Teleankenævnet" handles certain disputes between end consumers and providers of certain telecommunications services. Find out more about Teleankenævnet's authority and other requirements governing the filing of complaints at
Germany Conciliation Board of the Federal Network Agency for Electricity, Gas, Telecommunications +49 228140
[email protected]
Ref. 216 Schlichtungsstelle Postfach 80 01 53105 Bonn No additional information
Ireland Commission for Communications Regulation (ComReg) +353 1 8049600
[email protected] / [email protected]
Block DEF, Abbey Court, Irish Life Centre, Lower Abbey Street, Dublin 1 No additional information
Italy Comitato Regionale per le Comunicazioni (Co.Re.Com.) n/a There is one Co.Re.Com. in each Italian Region. The customer should contact the Co.Re.Com. in the region where he is resident or where the offices are located.
Netherlands ACM (Authority for Consumers and Markets) +31 70 7222 000
PO Box 163262500 BH Den Haag No additional information
Portugal ANACOM – Autoridade Nacional de Telecomunicações 800206665 (De Segunda a Sexta-feira: das 9h00 às 16h00)
[email protected]
Av. José Malhoa, n.º 12,1099-017 Lisboa No additional information
Spain SETSI 901336699
Gobierno de España. Ministerio de Industria Turismo y Comerci P. de Castellana, 160, C.P. 28071 Madrid , Madrid, España . No additional information
Switzerland Federal Communications Commission (ComCom) +41 313235290
[email protected] /
Marktgasse 9CH-3003 Bern No additional information

If you have taken the steps outlined above but are still concerned, you can file a complaint with your National Regulatory Authority:

Ombudsman information by country

United Kingdom Office of Communications (OFCOM) 020 7981 3040 or 0300 123 333, [email protected] or Ofcom Contact Centre, Riverside House, 2a Southwark Bridge Road, London SE1 9HA Ofcom cannot alter an Otelo decision, nor can Ofcom ask for the decision to be reviewed.
Austria Broadcasting and Telecom Regulatory GmbH ("RTR") 0810 511811 (EUR 0.07267/minute) Monday to Friday, 8am - 5pm Webformular unter: Broadcasting and Telecom Regulatory Licensing Office Mariahilfer Straße 77-79 1060 Vienna Deadlines can be provided for the responsibility of the RTR, which you must comply with, otherwise your request will not be processed: please inform yourself immediately upon receipt of our execution on the existence of such deadlines.
Belgium BIPT / IBPTBelgian Institute for Postal Services and Telecommunications Institut belge des services postaux et des télécommunications +32 (0) 2 226 88 88 [email protected] www.ombudsman BIPT - Ellipse Building - Building C - Boulevard du Roi Albert II 35 - 1030 Brussels N/A
Denmark N/A N/A N/A The Danish complaints body “Teleankenævnet” will forward complaints to other Danish complaints bodies as appropriate. If no relevant complaints body exists the customer can opt to take legal action through the competent courts.
France Regulatory Authority for Electronic Communications and Posts (ARCEP) +33 140477000 [email protected] Regulatory authority for electronic communications and substations7, Square Max Hymans 75730 PARIS Cedex 15 N/A
Germany Federal Network Agency for Electricity, Gas, Telecommunications, Post and Railways +49 228140 [email protected] Tulip field 453113 Bonn N/A
Ireland Commission for Communications Regulation (ComReg) +353 1 8049600 [email protected] or [email protected] Block DEFAbbey Court Irish Life Centre Lower Abbey Street Dublin 1 N/A
Italy Authority for Communications Guarantees (Agcom) +39 081 7507111 or +39 06 69644111 [email protected] Centro Direzionale, Isola B5Torre Francesco 80143 Naples Prior to engaging Agcom the customer must contact the competent Co.Re.Com. and go through with their mediation procedure.
Netherlands OPTA (Independent Post and Telecommunications Authority) +31 70 315 35 00 Please refer to to fill in online form Zurichtoren Muzenstraat 41 2511 WB The Hague N/A
Portugal ANACOM - Autoridade Nacional de Telecomunicações 800206665 (Monday to Friday: 9am to 4pm) [email protected] Of. José Malhoa, n.º 12,1099-017 Lisbon N/A
Spain N/A N/A N/A The Spanish regulator SETSI only deals with operators and not with customer complaints.
Sweden The National Post and Telecom Agency (PTS) +46 8 678 55 00 [email protected] Box 5398102 49 Stockholm N/A
Switzerland Federal Communications Commission (ComCom) +41 313235290 [email protected] Marktgasse 9CH-3003 Bern N/A